Impedance spectroscopy characteristics of nano ZnO doped liquid crystal/polymer film

Abstract

In this paper, the electrical impedance spectroscopy characteristics of polymer dispersed liquid crystal (PDLC) doped with nano-zinc oxide rods and its sensing applications are studied. Polymer dispersed liquid crystal films have the characteristics of stable structure, resistance to mechanical impact and easy preparation. By doping nano-zinc oxide rods into the material, the sensing function of polar molecules such as ethanol gas can be realized through the analysis of electrical impedance spectroscopy. In this paper, the complex impedance spectra of thin films encountering ethanol molecules are studied and analyzed through comparative experiments. In addition, the electrochemical equivalent circuit was established and analyzed. It was found that the film could sensitively and effectively realize the sensing function of the ethanol molecules. The sensitivity and response time of the sensor are further analyzed and studied. The experimental study and analysis show that nano-zinc oxide rod doped PDLC film is expected to be used as a gas sensor for detecting polarity of ethanol and other materials. It has the advantages of high sensitivity, stable structure, high repeatability, and easy fabrication.